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On March 28, 2012, 49 former NASA astronauts, scientists, engineers, and administrators sent a letter to NASA administrator Charles Bolden Jr. The letter requested that NASA in general and the Goddard Institute for Space Studies (GISS) in particular stop publishing the scientific conclusions about the human-driven causes of global climate disruption. The letter was filled with no less than six serious errors regarding the science, data, and facts of climate science. The errors, in turn, exposed that the signers had confused their fame and/or their expertise in unrelated fields with expertise in climate science. And in response, NASA’s chief scientist politely suggested that the letter’s authors and signers should publish any contrary hypotheses and data in peer-reviewed scientific journals instead of trying to censor the publication of scientific conclusions from NASA climate scientists.

The first error

The first error in the letter is that the authors and signers deny that “empirical data” shows “man-made carbon dioxide” is having an impact on global climate disruption:

We believe the claims by NASA and GISS that man-made carbon dioxide is having a catastrophic impact on global climate change are not substantiated, especially when considering thousands of years of empirical data.

In reality, “thousands of years of empirical data” do substantiate the claim that man-made carbon dioxide (CO2) is driving global climate change. Michael Mann, Ray Bradley, and Malcolm Hughes demonstrated that modern warming of the Northern Hemisphere was very likely greater than at any period in the last 2000 years first in 1999, then again in 2008, and it’s been verified repeatedly by independent researchers Wahl and Ammann in 2007, Huang et al in 2000, Smith et al in 2006, and others.

Not only have multiple independent researchers demonstrated that global temperatures are likely greater than at any period in the last 2000 years, but the data used by researchers are all independent too. Sources as varied as marine sediments, corals, tree rings, stalagmites, boreholes, the length of glacial tongues, ice cores, and lake sediments all independently confirm that modern global temperatures are anomalously high. Independent researchers using independent data and methodologies to reproduce the each other’s results is the ideal for how to conduct good science.

Similarly, scientists have analyzed the effects of CO2 on the balance of energy in the Earth’s climate system and found that CO2must be having a major effect. If it wasn’t a major driver of climate disruption, several well established physical laws would have to be wrong (conservation of energy, for one). For more information on this, S&R has some posts on this subject, both in reference to the Earth’s carbon cycle and Venus’ greenhouse effect. An even better high level overview is available from Skeptical Science.

The second error

The second error is that only a few climate scientists have declared that they deny the science underlying human-driven climate disruption, not the “hundreds” the letter claims. While the letter doesn’t provide any support for this allegation (yet another serious error), this is likely a reference to Oklahoma Senator James Inhofe’s December 2008 “Senate Minority Report” of about a supposed 700 scientists who deny human-driven climate disruption. The Center for Inquiry performed a detailed analysis of Inhofe’s list and discovered that:

Slightly fewer than 10 percent could be identified as climate scientists. [about 70]

Approximately 15 percent published in the recognizable refereed literature on subjects related to climate science. [about 135]

Approximately 80 percent clearly had no refereed publication record on climate science at all. [about 560]

Approximately 4 percent appeared to favor the current IPCC-2007 consensus and should not have been on the list. [about 28 – notes added by editor]

The third error is the letter’s reference to “tens of thousands of other scientists” who supposedly deny climate disruption. Unlike the vagueness of the second error, this reference can only mean one list, namely the list of approximately 31,000 alleged scientists collected by the Oregon Institute of Science and Medicine. While S&R debunked this list in detail three years ago, it’s worthwhile to reiterate a few key points from the original post:

The OISM’s criteria are so broad that nearly anyone with a Bachelor of Science degree is eligible to call him or herself a “scientist.” It doesn’t matter whether you work in a scientific field, whether you’re an engineer instead of a scientist, or even if you’re a stay-at-home Mom or Dad with an unused degree – if you’ve got a BS degree in one of a large number of fields, you’re a “scientist.”

Even if we assume that a mathematician, nuclear engineer, or veterinarian should qualify as a “scientist,” using the OISM’s own criteria produces over 10.7 million “scientists” who have graduated from US universities since 1970. The OISM’s 31,478 so-called scientists represents 0.3%, or one out of every 340 scientists. That’s an insignificant minority.

The OISM list contains only 152 atmospheric scientists, or 2.1% of the American Geophysical Union’s members who are atmospheric scientists.

The OISM list contains only 22 hydrologists, or 0.4% of the AGU’s hydrology group membership.

The OISM list contains only 341 meteorologists, about 2.4% of the American Meteorological Society’s membership.

The OISM’s list of names would be laughable if people didn’t refer to it in a naive or dishonest attempt to deny the remarkable agreement among climate scientists (and actual scientists in general) about the human-driven nature of climate disruption.

Coincidentally, the 49 former employees who signed the letter represent about 0.3% of the current headcount at NASA, never mind the between 54,000 and 102,000 people NASA has employed since it was created in 1958. As with the OISM list, 0.3% is an insignificant minority.

The fourth error (updated)

The fourth error is that the letter twice uses the subjective, unscientific term “catastrophic” in reference to climate disruption.

Scientists don’t use the term “catastrophic,” and there’s a good reason for that: try to define exactly what you mean by “catastrophic” in an objective way. Whether something is a catastrophe or not is a matter of opinion, and no scientist involved in climate would ever use such a subjective term to describe something that is objectively scientific. It’s probably fair to say that most scientists would view the end of all life on Earth as a catastrophe, but what about sea level rise that drives millions of people out of their low-lying homes? That would be a catastrophe for the resulting climate refugees, but is it “catastrophic” in a scientifically objective way?

The term “catastrophic” is used almost exclusively by people who oppose adaptation and/or mitigation of the projected outcomes of human-driven climate disruption, and it’s used in an attempt to make climate scientists appear biased or extreme. Actual climate scientists, on the other hand, simply describe what they project will occur in an objective manner, just as unbiased scientists should.

The fifth error

The fifth error is that the letter claims that there hasn’t been a “thorough study” of “natural climate drivers.”

[W]e feel that NASA’s advocacy of an extreme position, prior to a thorough study of the possible overwhelming impact of natural climate drivers is inappropriate.

Natural factors in climate change – solar variability, Milankovic cycles, volcanism, El Nino, even cosmic rays – have been investigated very thoroughly, and none of the natural factors are capable of generating the observed disruptions in the global climate. The impacts of natural drivers on climate disruption have been investigated repeatedly and in detail, as the two figures (from the Skeptical Science website) below show.

Human vs. natural percent contributions to climate disruption over the past 50-65 years according to various peer-reviewed studies.

That’s 13 different ways we know that human activity is driving global climate disruption, and six major peer-reviewed scientific papers that describe just how much is driven by human activity vs. natural factors.

The letter’s authors and signers seem to want NASA to censor the publication of scientific conclusions about human-driven climate disruption until scientists are 100% certain the conclusions are correct. This is more than just unrealistic – it’s impossible. It’s impossible to guarantee anything in science or engineering to 100% certainty, and as former employees of NASA, every one of the authors and signers knows it instinctively: Apollo 1, Apollo 13, Challenger, and Columbia, just for starters.

Anyone who works for NASA – or, like I do, works for a NASA subcontractor – lives and breathes the fact that nothing can be guaranteed to 100%. Any former NASA employee who has forgotten this should be ashamed of themselves.

The sixth error

The sixth error is that the letter claims NASA is making “unproven” and “unsupported” remarks about climate disruption and asks NASA to not make any more. The analysis of the five prior errors shows just how wrong this really is – there’s a massive amount of proof and support that human activity, namely burning fossil fuels and agriculture, are the primary driver of climate disruption. But in case there’s any question of that, here’s a link to Skeptical Science’s list of climate myths, with detailed rebuttals supported by referenced peer-reviewed scientific papers in reputable journals: Taxonomy of Climate Myths.

And in case that’s not enough, we can recount a few of the established physical laws and properties of CO2 that would all be wrong if human activity wasn’t the dominant driver of climate disruption today:

Conservation of energy

Conservation of mass

Quantum mechanics

Vibrational modes of CO2

Radiative transfer

Isotope ratio science for carbon-12, carbon-13, and carbon-14

Radioisotopic dating

et al

And that’s just a short list. The man-made nature of climate disruption is based on so many well established, basic physical principles that it can’t be rationally disputed without shattering large portions of modern science (physics, chemistry, biology, and geology just for starters) and ignoring most of the modern technology (GPS, IR cameras, heat-seeking missiles, weather satellites, etc.) that was successfully designed and built using that science.

As serious as all those errors are, each and every one of them can be corrected with education and experience. Of greater concern is the underlying causes of the errors, namely two related shortcomings on the part of all the letter’s authors and signers – the belief that their fame or their expertise in other fields automatically granted them authority to comment on climate science.

Mission Operations Control Room, April 13, 1970 (Apollo 13, just prior
to the explosion)

Fame is no substitute for expertise

Many of the 49 former NASA employees are famous for one reason or another. I counted seven who were astronauts. Gerald D. Griffin and Joe Kerwin were both part of the team that got Apollo 13 home safe, and Griffin was also the Director of the Johnson Space Center. Christopher C. Kraft developed NASA’s Mission Control concept and also served as the Director of Johnson Space Center.

But while fame occasionally comes as a result of expertise, expertise is never a result of fame. If you’re not sure about this, ask yourself the following question: would you want Paris Hilton landing your commercial airliner? How confident would you be if NASA installed Snookie in Mission Control? Would you trust your retirement to George Clooney?

In reality, fame grants one thing – attention. When a celebrity speaks, people listen, even if people shouldn’t. In fact, the organizers of this letter (most likely Harrison Schmitt and/or Walter Cunningham) relied on their fame as astronauts to get Fox News, Marc Morano, the Huffington Post, Anthony Watts, the Houston Chronicle and others, to report on and repeat verbatim many of the letter’s naive or dishonest statements regarding climate.

Albert Einstein was the expert in relativity, and he earned his fame partly as a result of that expertise. But Einstein’s fame merely meant that people listened when he spoke, not that he was an expert on every subject on which he spoke. [See Ed. note below] In fact, he famously denied some of the weirder implications of quantum mechanics that have since been observed. Nikola Tesla claimed that relativity was something whose “exponents are brilliant men but they are metaphysicists rather than scientists,” yet relativity has also been demonstrated. Lord Kelvin, developer of the concept of absolute temperature, denied scientific data and theories that demonstrated that the Earth’s age was older than 20-40 million years. Harold Jeffreys, one of the geologists who proved that the Earth’s outer core was molten, rejected plate tectonics entirely.

Those four scientists were justifiably famous, and all were brilliant scientists in their areas. But that doesn’t mean that they didn’t make mistakes, and it doesn’t mean that they always accepted the latest and best science. Each of them denied scientific theories that have since become mainstream scientific thought.

Similarly, many of the former NASA employees who signed the letter earned their fame, but they’re no more experts in climate science than Einstein was in quantum mechanics or Tesla was in relativity. The large number of errors in such a short letter (227 words in four paragraphs) demonstrates that the former NASA employees do not understand climate disruption and no amount of fame, however well earned, can change that fact.

Expertise is non-transferrable

But even more important than the issue of fame is the fact that expertise in one field does not make anyone an expert in a different field, even one that’s closely related. I’m an expert in designing electronics to convert light and temperatures into digital data that a computer can use, but that doesn’t make me an expert at designing the computer itself, the networking equipment used to move that data around, or the antennas used to transmit it from a satellite to the ground. The skills I have that are broadly applicable to all of electrical engineering give me a leg up in designing computers, networking equipment, and antennas, but only years of experience could make me an actual expert.

Given my electrical engineering expertise doesn’t make me an expert in every field of electrical engineering, I certainly can’t claim that my electrical engineering expertise makes me an expert in climate science. If I want to claim expertise in climate science, I first have to prove that I have somehow acquired the knowledge and skills of a climate expert.

None of the letter’s authors or signers have any expertise in a climate-related field, and they’ve offered no proof that they have independently acquired the necessary expertise. Expertise in the effects of high levels of carbon dioxide on astronauts doesn’t make one an expert on CO2‘s effect on ecosystems. Expertise in lunar geology doesn’t make one an expert in geochemical sequestration of atmospheric carbon dioxide. Expertise in heat transfer through space shuttle heat tiles doesn’t make one an expert in heat transfer between the Earth’s surface and the atmosphere. Even expertise in weather forecasting doesn’t make the forecaster an expert on climate.

No amount of expertise on one subject can magically bestow expertise on any other subject. Expertise must be earned through dedicated effort day in and day out, over the course of years. And there’s no evidence that any of the letter’s authors and signers have earned any climate expertise.

Think about this for a moment. If you were in charge of the safety of the space shuttle upon re-entry, who would you listen to first – an electrical engineer like me, or an expert in the shuttle’s ceramic heat tiles? Unless I could prove that I knew what I was talking about, you’d correctly ignore my advice and listen to the actual expert.

So why would you listen to an expert on heat tiles – or medicine, or lunar geology – when he’s writing a letter about climate science? Especially a letter that is packed full of obvious, naive or dishonest errors.

NASA’s response to the letter

NASA’s chief scientist, Waleed Abdalati, published a short response to the letter. In it, Abdalati wrote that “NASA does not draw conclusions and issue ‘claims’ about research findings” that NASA researchers conduct. Instead, NASA “strongly encourage[s] scientists to communicate” the results of their research “after these studies have met the appropriate standards of scientific peer review.” Abdalati also said

If the authors of this letter disagree with specific scientific conclusions made public by NASA scientists, we encourage them to join the debate in the scientific literature or public forums rather than restrict any discourse.

In other words, put up or shut up. Clearly NASA doesn’t have the same concerns about the scientific conclusions of their scientists that these former NASA employees do.

So why did the 49 former NASA employees sign this letter filled with naive or dishonest claims against NASA and the researchers at GISS? Without asking each and every signer, it’s impossible to say beyond guesswork. Perhaps the signers were misled by the authors. Perhaps they’re concerned about budget cuts gutting manned space flight more than it already has been (all the signers are from Johnson Space Center in Houston, where Mission Control is located). Perhaps they’re merely ignorant of how much elementary science would need to be wrong in order for human-driven climate disruption to be incorrect.

Or perhaps it’s as simple as they said in the letter: “At risk is damage to the exemplary reputation of NASA, NASA’s current or former scientists and employees….” Abdalati’s excellent response makes it clear that NASA’s exemplary reputation is intact, as is the reputation of NASA’s current employees.

Unfortunately, the same cannot be said of the reputations of these 49 former NASA astronauts, scientists, engineers, and administrators.

[Ed. Note (4/26/12): A quantum mechanics researcher pointed out to me in an email that my point about Einstein isn’t quite accurate – Einstein was one of the many co-developers of quantum mechanics, so he was an expert in the subject, even if did reject quantum entanglement.]

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Spot on. I read the letter and just felt sorry for the signers. Unfortunately, denialism is less about refuting the science than creating the perception of uncertainty in the science in order to manipulate public perception.

Einstein didn’t reject quantum entanglement, he argued against it. There’s a big difference. Einstein was properly skeptical, he never was a denier, so its not ok to put him in the same company as the authors of this letter. Interestingly, Einstein was a major contributor to furthering understanding of this phenomenon, for example he co-authored the famous EPR paper.

“no more experts in climate science than Einstein was in quantum mechanics” is nevertheless a profoundly historically-inaccurate statement. Abraham Pais, who should know a thing or two, considered Einstein’s contribution to quantum mechanics to be his most profound and revolutionary work, and that the Nobel Committee was actually right (although for the wrong reason) to award him the prize on that basis. Einstein’s critique of QM, however misguided it may have been, was made from a position of knowledge, not ignorance. (In that respect like Harold Jeffreys).

The lesson to be learned is that you have to judge everyone on the quality of their arguments, not on their reputation. That’s why, for example, your blog carries more weight than the letter from the 49, even though you are no more a climate scientist than they are.

Colin, as I pointed out in the note above, I have been corrected on whether or not Einstein was an expert, and I admit to screwing that one up. I was clearly too enamored of his rejection of entanglement to remember that one of my favorite things is reading about research into Bose-Einstein condensates, and when that popped up in my email yesterday, I had a face-palm moment.

Your point about the quality of the argument is critical, especially since in science, the quality of an argument is less about rhetoric and more about the strength of the data, clarity of logic in explaining how the data connects to a theory or hypothesis, and so on.

I think that this whole Einstein discussion has made another point as well – even experts can be so wrong about something that they deny it for some other, non-science-based reasons. It’s my opinion that Einstein was like that with entanglement. While most would agree that Richard Lindzen is a climate expert (although he has a long history of having his peer-reviewed papers disproved on him within mere months, which is nearly instantaneous in publication time), he also denies that human activity is the overwhelming driver of climate disruption.

Sometimes it seems that our ideas of “how things are” gets in the way of personal growth when things turn out to be different. I think this is human nature in some cases, personal arrogance in others, and unfortunate in every case.

How very odd signatory Larry Bell , who bills himself as a “Professor of Space Architecture” in his Forbes column should self-demote to retiree as a ” 32 years Manager, Crew Systems” at the the JSC. The letter’s definition of ‘scientist’ evidently encompasses the astronauts valets.

RE: 1st Error} Apparently, among other things, this alludes to [seeks to validate] Mike Mann’s disputed hockey stick graph that diminishes, if not eliminates, the significance of the MWP {circa 950 – 1200ACE & the LIA {circa 1400 – 1800ACE}. It’s well documented that for 250 – 300yrs Greenland’s Ice sheet receded significantly during the MWP but then expanded again w the on-set of the LIA. Today this type recession is held as evidence of Globalized Warming while currently being minimized, if not denied, for the same during the MWP.
Also confirmed here is the link between Hansen based green-house effect global-warming models to Hansen’s earlier Venusian run-away ‘Green-house’ effect models RE Venus. BUT- EARTH AIN’T VENUS!

RE: 2nd Error} FYI: Jim Hansen was NOT originally a climate-scientist & IPCC head RK Pachuari is definitely NOT one! – This also seemingly alludes to the non-scientific term consensus {The over-whelming consensus among scientists is for man-made CO2 caused global-warming- Al Gore: ‘Inconvenient Truth’}.
Also some presumptuous errors are made here- see below.

RE- 3rd Error} It’s being asserted & presumed that these ex-NASA folks are using these sited lists without actually confirming that this is actually the case! Thus the ready-made attack here vs these lists that may not even apply!
It’s also being insinuated here that these ex-NASA folkss are out-right man-made CO2 caused global-warming deniers, when they actually only indicate that they are skeptical of &/or dispute that the matter has actually been fully ‘substantiated’ {= PROVEN}- AND They insist that GISS should rely more so on actual empirical data collection & analysis rather than {Hansen based green-house effect climate} modeling!

RE: 4th Error} Poses an objection to the non-scientific term catastrophic [NOTE: Scientific ‘consensus’ is often being used &/or implied in standard climate-change discourse- Yet Consensus is a Political Term- NOT a Scientific Term] -HOWEVER- When Jim Hansen, the IPCC & Al Gore, et-al- go from predicting 450 – 500 ppm CO2 to 800 – 1000ppm by the end of the 21st century {said to the be highest atmospheric CO2 content in 20 – 30 Million YRS}; – & estimates for aver global temps by 21st century’s end go from 2*C to 6*C to 10*C; – & increased sea level estimates go from 10-20cm to 50-60cm to 1M – 2M { which would totally submerge the Maldives & partially so Bangladesh}; – predictions of the total melting of the Himalayan Ice caps by 2050, near total melting of Greenland’s ice sheet & partial melting of Antarctica’s ice sheet before the 21st century’s end ; – massive crop failures; – more intense & frequent hurricane {ala Katrina} for much longer seasonal durations, etc, etc, etc… – IMO That’s Sounds pretty damned CATASTROPHIC to ME! The $1Million question is can all these dire predictions be substantiated??!!

RE: 6th Error} The standard for expertise in a climate related field [Expertise in Venus’ atmosphere does NOT necessarily make one an expert on the effects of trace CO2 in Earth’s atmosphere]- initially would have eliminated NASA-GISS Dir Jim Hansen whose expertise was on Venus’ theorized run-a-way green-house effect – a model which he then applied to theorize CO2 caused green-house global-warming on Earth. Yet Hansen initially had no particular expertise in climate science, meteorology, oceanography, earth & environmental science, etc. And this standard most definitely applies to IPCC head Pachuari!

RE: Rebuttal to 2nd Error: } The over-whelming ‘consensus’ of the experts agree that man-made CO2 is causing global-warming… – Al Gore ‘Inconvenient Truth'{:
The standard line is that 97% of climate experts agree on w this premise [alluded to by this rebuttal to the 49 ex-NASA astronauts’ & scientists’ letter of complaint to NASA] . BUT- Let drill down on this over-whelming ‘consensus’ argument.

}Between March 19 thru May 28, 2007 Harris Interactive conducted a mail survey of a random sample of 489 self-identified members of either the American Meteorological Society or the American Geophysical Union who are listed in the current edition of American Men & Women of Science. [Note this is less than 500 climate experts = just 10Xs more than these 49 ex-NASA ‘dissenters’ – Yet you constantly hear of 1000s / 10,000s of climate experts agreeing in an over-whelming ‘consensus’.]
97% of the climate scientists surveyed believe “global average temps have increased” during the past century
84% say they ‘personally believe’ [implies they may NOT have actually studied the matter – IE: are NOT experts on the topic] human-induced warming is occurring, & 74% agree that “currently available scientific evidence” substantiates its occurrence.
54% ‘believe’ the warming measured over the last 100 yrs is NOT “within the range of natural temperature fluctuation” [means that 46% thinks that it is within the Natural Range] – 56% see a 50-50 chance that global temps will rise 2*C or more during the next 50 to 100 yrs.
Based on current trends, 41% of these scientists believe global climate change poses a very great danger to the Earth in the next 50 to 100 yrs, compared to 13% who see relatively little danger. Another 44% rate climate change as moderately dangerous.
Only 29% express a “great deal of confidence” that scientists understand the size & extent of anthropogenic [human] sources of greenhouse gases,” & only 32% are confident about our understanding of the archeological climate evidence [It is no small matter that only 1/3 of climate experts are confident in proxy data RE: Earth’s past climate!].

Summing up 97% of these 489 climate experts agreed that generally aver global temps got warmer during the 20th century, but just 3/4 of them are certain that the evidence shows man-made CO2 is THEE MAIN Factor. And only a bit more than 1/2 of them think that global temps are beyond the natural range. Seems like this consensus is not quite so over-whelming after all!

Thank you for taking the time to comment so extensively. I’m afraid, however, that you appear to have made a number of general issues and specific mistakes in your response. I’ll cover the general issues with your comment first, and then move to the specific mistakes you made that need correction.

First, you failed to link to a primary source for your claim that the “Greenland’s Ice sheet receded significantly during the MWP.” Simply stating that “it’s well documented” is not sufficient for a reasoned, intelligent debate on the subject. For the purposes of argument, I’ll acknowledge that it likely did so, but as the person who brought it up, the onus is on you to demonstrate that the amount the ice sheet receded during the Medieval Climate Anomaly (MCA) is similar to the amount it has receded in modern times. If, for example, the evidence indicates that the modern recession has been faster or greater than it was during the MCA, that evidence would actually undermine your claim.

Similarly, you should provide links (or make it clear in written form) where you got your other information from. That way the reliability of your sources as well as the accuracy of your claims could be assessed. Thanks.

Second, it’s clear from your response that you either failed to follow most of the links in the original post or that you failed to understand them when you followed them. One example is your conclusion that my mention of Venus’ atmosphere meant that I was discussing “run-away ‘Green-house’ effect models” as originally developed by James Hansen. But if you had actually followed or understood the link, you would have discovered that it is the first part of a 5-part series debunking various claims made by climate disruption deniers that Venus’ surface is extraordinarily hot due to some non-greenhouse effect cause. Another example is that you clearly failed to read or understand the portion of the OP titled Expertise is non-transferable, wherein I write that “expertise must be earned through dedicated effort day in and day out, over the course of years.” Regardless of his original background, Hansen has certainly met this criteria, as have many others whose original expertise was not in a climate-related field of study. Gavin Schmitt (computer scientist originally) qualifies as a climate expert according to this standard, as does Ray Pierrehumbert (electrical engineer originally).

As for your specific errors, I’ll go through those rather quickly.

First, you focus only on a single paper, the original Mann Bradley Hughes 1999 paper that I link above for reference, ignoring the fact that scientific methods and data have advanced considerably in the last 13 years, as indicated by the four other papers I reference.

Second, you misuse the word “allude,” which means “to make indirect reference, when I in fact link to it directly. Not only that, your bracketed “[seeks to validate]” implies that an allusion seeks to validate, when that is in fact not the case. Words have specific meanings and definitions – please use them correctly.

Third, while you correctly note that I didn’t contact the letter’s author(s) to acquire their specific references, one of my points was that I should not have needed to do so in the first place. I wrote in the OP that “the letter doesn’t provide any support for this allegation (yet another serious error) [emphasis added].” As I point out, however, multiple independent public opinion polls have attempted to determine the level of scientific consensus among varying levels of experts (scientists in general, climate scientists in particular, climate “super-experts,” etc.) and the results of each and every poll tells the exact same story – the letter’s authors are wrong.

Fourth, I’m not insinuating anything about the signatories, except for the few that have demonstrated that they’re honest climate disruption deniers (such as Harrison Schmitt, who is a member of the deceptive, dishonest, and hypocritical Heartland Institute’s Board of Directors). I state explicitly in the conclusion of the OP

So why did the 49 former NASA employees sign this letter filled with naive or dishonest claims against NASA and the researchers at GISS? Without asking each and every signer, it’s impossible to say beyond guesswork. Perhaps the signers were misled by the authors. Perhaps they’re concerned about budget cuts gutting manned space flight more than it already has been (all the signers are from Johnson Space Center in Houston, where Mission Control is located). Perhaps they’re merely ignorant of how much elementary science would need to be wrong in order for human-driven climate disruption to be incorrect.

One possibility is ignorance. Another is misplaced trust. Another is a personal value choice. However, I specifically refuse to call someone a climate disruption denier until he or she has demonstrated their denial – only a few of the signatories have done so, and I’m explicitly not ascribing denial to the others.

Fifth, your claim that the word “consensus” is not a scientific term is not necessarily accurate. The word “consensus” has two definitions, only one of which is clearly “political” in nature:

1a: general agreement: unanimity

1b: the judgment arrived at by most of those concerned

2: group solidarity in sentiment and belief

Definition 2 is clearly political, but neither of 1a or 1b are. Scientific “consensus” would be the 1b definition – the judgement at by an overwhelming majority of scientists. And scientists strive to arrive at their judgements via data, rather than via belief.

Sixth, I must thank you for making my point about the non-scientific nature of the word “catastrophe” for me. I wrote in the OP that “Whether something is a catastrophe or not is a matter of opinion, and no scientist involved in climate would ever use such a subjective term to describe something that is objectively scientific.” Your response was to detail a long list of objective projections and then to apply the term “catastrophic” to them – “IMO That’s Sounds pretty damned CATASTROPHIC to ME!” The fact that you had to resort to “IMO” and “to ME!” indicate that you realize, perhaps unconsciously, that you’re making a subjective judgement about objective projections,

But allow me to put this another way. You mention how sea level rise is projected to partially submerge Bangladesh, and how “catastrophic” that would be. I’m certain that it would be catastrophic to the Bangladeshis affected, but what about the Greenlanders who would benefit from a longer growing season, more arable land, and the higher standard of living available as melting ice sheet and less Arctic sea ice exposes natural resources to exploitation and brings trade? For the Greenlander, climate disruption might well be a godsend, not a catastrophe.

Seventh (here down relates to your attempt to spin the results of the STATS survey from 2008), you seem to suggest that finding only 489 respondents to the survey implies that the scientific consensus is being inflated. But according to the AGU’s membership page, the AGU alone has over 60,000 members who are “Earth, atmospheric, oceanic, hydrologic, space, and planetary scientists,” never mind the additional people who are members of the AMS or other scientific organizations.

Eighth, you don’t seem to understand just how significant it is that such a large number of climate scientists (84%) reaching a consensus that “human-induced warming is occurring.” If you assume that there are 100,000 climate scientists in the world (there’s not that many, but it’s a convenient number that makes a critical point), that the results are accurate to 4% as per the STATS page you link to, and that the population size is 489 (as per the STATS survey), the confidence level is 98.44%. This means that there is only 1.56% chance that the conclusion is outside of the 80-88% window when applied to the entire population of 100,000 climate scientists. That’s a pretty low chance of error.

Ninth, you missed the fact that the STATS writeup regarding “confidence” in the scientific understanding is a partial description of the results. The paragraph you somewhat paraphrased reads, in its entirety

Only 29% express a “great deal of confidence” that scientists understand the size and extent of anthropogenic [human] sources of greenhouse gases,” and only 32% are confident about our understanding of the archeological climate evidence.

Any answer that has wording like “great deal of confidence” was associated with a question that had 3 or 5 point scale ranging from “none” to “a great deal” of confidence. STATS reported only on the topmost point on the scale when they should have reported on the entire thing. For all we know, an additional 60% had “some confidence” – there’s no evidence one way or another.

Tenth, and last, it’s worthwhile noting that in 1991, only 41% of climate scientists were very confident that industrial emissions of greenhouse gases were responsible for climate disruption. But by 2008, when the STATS survey was taken, the number had risen to 74%. And what’s more, the STATS survey is in line with every other recent poll conducted to gauge the scientific consensus regarding the industrial and agricultural sources of climate disruption.

RE: MWP- It’s almost hard to take this objection seriously, but if you insist – you can start @ Wikipedia & drill-down to their supporting sources on the subject, &/or you can Google MWP.

RE: Venus’ Theorized Run-a-Way Greenhouse Effect- Though it seems likely that this scenario is involved somehow w why Venus’ environment is so hot, dry, barren & Harsh – that fact is NO-One actually knows for sure whether a run-a-way greenhouse effect caused these conditions or if these condition led to a run-a-way greenhouse effect [or some combo of both].
Take Antarctica- which is a whole lot closer & smaller & also far more inhabitable than Venus [though it’s never been inhabited in any significant numbers]. Yet there are still many things about Antarctica that’s unknown- for instance- even though scientific out-posts from various countries have been there since the at-least 1950s & 60s, the fact that Antarctica has sub-glacial lakes [the largest is the size of lake Erie but nearly 3Xs deeper] wasn’t confirmed till the mid-1990s. Now it’s confirmed that there are at-least 250 -300 of these sub-glacial lakes.
My Point: To assume we know all there is to know about conditions on Venus when we’re still discovering new facts about Antarctica is, IMHO, a bit arrogant.

RE: Your 2nd Objection: The reason I used the phrase} ‘Apparently, among other things, this alludes to [seeks to validate] Mike Mann’s disputed hockey stick graph…’{ – is because I didn’t want to be presumptuous & declare that you were saying something which perhaps you were not saying. But now that you’ve confirmed it…

RE: Your 4th Objection: Your quotes} ‘I’m not insinuating anything about the signatories…’ ‘Why did the 49 former NASA employees sign this letter filled with NAIVE &/or DISHONEST claims against NASA and the researchers at GISS?…’{
Pardon me if sounds like you’re ‘insinuating’ that this 49 ex-NASA astronauts & scientists of either being Naïve &/or Dishonest!
BUT- IMO these 49 most likely know a whole lot more about the inner-workings [& behind the scenes Ops] of Jim Hansen’s GISS than YOU [or I for that matter]. So I’m willing to consider that they might have some insider info that YOU AREN’T Privy To! But feel free to correct me if you’ve got a NASA insider hook-up!

RE: Catastrophic vs Consensus, You object to the use of the ‘un-scientific’ term catastrophic while I question the use of the un-scientific term ‘consensus’. I’ll leave it that.

RE: Greenland [population less than 60,000] & Bangladesh [population nearly 160,000,000]. Again it’s almost hard to take seriously that you’re saying that a situation that climate scientists say would likely Devastate much Bangladesh’s 160,000,000 people [IE: the melting of Greenland’s ice-sheet -> permanent flooding of much of Bangladesh] would be balanced by conditions that may [or may NOT] be beneficial to less than 60,000 Greenlanders!

RE: I worked on the 2000 US Census [in a technical capacity]- in which the US Gov’t is Constitutionally mandated to do a head-count [NOT sample] every single person in the US [at that time approx 285,000,000] every 10yrs. This was accomplished within 2 – 3yrs.
MY Point: IMO It should be possible to survey all 60,000 AGU folks within a yr- & certainly they could have fairly easily surveyed far more than 489 [IE: 6000 – 12,000]! Again 489 is less than 1% of 60,000 AGU members, & is just 10Xs more than these 49 ex-NASA astronauts & scientists who signed this letter objecting to Jim Hansen’s GISS’ over-reliance on climate-modeling to make dire future predictions.

RE: The Over-whelming scientific Consensus on man-made CO2 caused Global-warming- 97% of the climate scientists surveyed believe “global aver temps have increased” during the past century [So do I] – Your quotes: How ‘significant it is that 84% of climate scientists have reached a ‘consensus’ that “human-induced warming is occurring” ‘-}84% ‘personally believe’ [implies they may NOT have actually studied this topic – IE: may NOT be experts on this particular matter] human-induced warming is occurring{- … – ‘In 1991 only 41% of climate scientists were very confident that industrial emissions of greenhouse gases were responsible for climate disruption. But by 2008 the number had risen to 74%..’-}74% agree that “currently available scientific evidence” substantiates that “human-induced warming is occurring”{- …
So which is it? Is the number 97% [an over-whelming consensus], 84% ‘who personally think that maybe it’s so’, or 74% who agree that the scientific evidence implicates man–made CO2 as the main culprit?
IMHO The reason that they generally say 97% [an over-whelming consensus] rather than the 74% is because- while 74% is a definite majority- It’s Definitely NOT an OverWhelming Consensus!
To Illustrate the Point: During the run-up of the 2003 Iraq invasion, main-stream polls said that 75% of Americans were sure that Saddam had WMD’s & was linked w Al-Qaeda RE 9-11- which implies that only 25% in the US either doubted it or at-least were NOT fully convinced & that more evidence was need to make a conclusive decision. At that time some in the main-stream talked about an ‘Overwhelming consensus’ of Americans being convinced that Saddam had WMDs, or was in cahoots w Al-Qaeda on 9-11, or both. Well history has proven that the 25% that express some level of doubt about all of that hype from main-stream & Gov’t experts- Were IN FACT RIGHT!

From your article above: Fame Is No Substitute For Expertise} ‘Many of the 49 former NASA employees [actually ex-astronauts, administrators, scientists & technical specialists] are famous for one reason or another. 7 were astronauts. Gerald Griffin & Joe Kerwin were both part of the team that got Apollo 13 home safe, & Griffin was also Dir of the Johnson Space Center. Chris Kraft developed NASA’s Mission Control concept & also served as Dir of the Johnson Space Center.
While fame sometimes comes as a result of expertise [which basically is the case here], expertise is never a result of fame. Would you want Paris Hilton landing your commercial airliner? How confident would you be if NASA put Snoop Dogg in charge of Mission Control?
Fame gets attention. When a celebrity speaks, people listen, even if they shouldn’t. The organizers of this letter (most likely Harrison Schmitt and/or Walter Cunningham) relied on their fame as astronauts…’{

First of all to compare these 49 NASA astronauts’, administrators’, scientists’ & technical specialists’ letter criticizing the methodology of a DIVISION Of NASA [IE: Jim Hansen’s GISS]- to ‘trusting Paris Hilton to land a jet airliner’, is simply ridiculous!
2nd Walt Cunningham was a fighter pilot [as many/most NASA astronauts were/are jet pilots of some type] & has a MS is physics -&- Harrison Schmitt has a PhD in geology [beyond being astronauts], so it ain’t like they have no scientific & technical aptitude. FYI: To be a pilot you have know the basics of aerodynamics & meteorology- because understanding weather conditions & patterns & also wind-speed is crucial to flying [IE: the Challenger Disaster for which weather conditions played a critical role]. IMO Your dismissal of this fact in this debate is a bit curious…, BUT Your attempt to compare their level of knowledge on this subject to that of ‘Paris Hilton piloting a jet airliner’ is more than curious- it’s out-right insulting!

And if we’re going to use the standard of expertise in climatology [&/or meteorology, oceanography, & earth & environmental science] before one is ‘qualified’ to speak on the subject of Global-warming / climate-change, then pray tell how does this apply to Mr ‘Inconvenient Truth’ Al Gore, who is a politician, lawyer & Vietnam Vet –YET- has NO particular expertise in any scientific or technical field??!! The phrase Global-Warming / Climate-Change & Mike Mann’s disputed ‘Hockey Stick Graph, likely became house-hold terms [at-least in the US] due to Al Gore’s ‘Inconvenient Truth’. So why did the folks behind ‘Inconvenient Truth’ pick Gore as their front man? IMO- Because Gore is a well-known [IE: celebrity / famed] politician who many/most believe should have been POTUS in 2000! BUT- He’s no climate-expert! So should we then just dismiss the Academy Award Winning [= fame / celebrity] ‘Documentary’ ‘Inconvenient Truth’ out of hand???

Nixak, I must not be sufficiently clear in my explanations, so I’ll try again.

With respect to the MWP and providing links, I was specifically asking you to provide a specific link to support your claim that the GIS retreated as far during the MCA as it has today, and at a similar rate, not for a discussion about the existence of the MCA or argument about whether or not the MCA was global in extent. You made a specific claim, you should have supported it. Please take this opportunity to do so.

As for your point about the runaway greenhouse effect, again, if you’d read the posts I wrote, you’d know that they don’t talk about “runaway” greenhouse warming at all. They’re about what’s keeping Venus so hot today, not how the atmosphere got this way. And they demonstrate pretty conclusively that the only physically viable explanation is the greenhouse effect. I don’t care about whether runaway greenhouse warming or volcanism or a celestial impact was what caused the atmosphere to become so dominated by CO2, only that CO2is keeping Venus’ surface hot. Your focus on something that I haven’t talked about at all strikes me as a distraction, nothing more.

I do, however, agree with you that we don’t know everything there is to know about Venus. But a) that’s irrelevant here and b) some things about Venus’ atmospehre are known with great detail. The fact that the greenhouse effect is responsible for Venus’ high surface temperature is one of those things.

With respect to your objections to the hockey stick, you’re clearly trying to make a point here, so why don’t you just come right out and say it.

There’s a difference between the content of a document and the motivations for why someone would sign the document, and you’re equating the two. Just because the content of the letter contains naive and/or dishonest claims doesn’t mean that all the signers are naive and/or dishonest, only that whomever wrote the document was naive and/or dishonest. Everyone else could simply be too trusting of a personal friend who has an axe to grind. It happens.

And the inner workings of GISS aren’t the point, Nixak. The letter specifically criticizes GISS in particular and NASA in general for making claims that the signatories incorrectly contend are unproven on “public releases and websites” (first and last paragraphs of the letter – the link is at the top of the OP). The letter itself limits its scope to public statements, not private deliberations.

Regarding “consensus,” if you want to argue that the definition of “consensus” should be qualified (since definition 1b permits a mere majority to meet the definition), I’ll accept that. The point at which a “majority” moves to a “consensus” is a subjective point – 60%, 80%, 99.999999%, or whatever – but the fact is that the definition objectively means no less than 50%+1 of any group that come to a judgement. This point is not arguable.

You’re trying to make more of the Bangladesh vs. Greenland argument than it really deserves. Let me try to make my point using a smaller example and maybe that will help. If my home burns down, it would qualify as a catastrophe for me and my family. But it’s not a catastrophe for my insurance company, it’s just another standard homeowner claim to be processed. And the destruction of my home is a boon to whatever construction company gets the contract to rebuild my house.

Every catastrophe produces benefits for someone or something even as it destroys someone or something else. Which is why the phrase “catastrophe” cannot be used in a objectively scientific manner. If you prefer a simple aphorism, the one that applies is “one man’s trash is another man’s treasure.” The same is true of sea level rise, changes in rainfall patterns, and so on – someone or something always benefits. And that’s why the term “catastrophic” can’t be used in a scientific manner.

To be fair, I can think of one case where “catastrophe” could be used scientifically – the death of the universe. But shy of that, even the death of our species or our sun going nova will benefit someone or something, somewhere.

Regarding the scientists, you haven’t addressed my point at all, which is that surveys regularly use small samples to predict the response of large populations, and it works. If you have issues with the methodology of the STATS survey, then take it up with STATS and the author Richard Lichter, not me. And don’t forget the many other surveys that have been done in parallel with STATS, all of which show an overwhelming consensus (STATS is the low outlier, but when I asked for the list of questions three years ago, they were not available, something I think casts doubt on the conclusions as published on the web).

If you prefer, look at the Pew survey from 2009, which surveyed 2533 AAAS members and found that 84% of scientists thought climate disruption was due to human activity and 92% thought it was a “somewhat” or “very” serious problem. Or Doran et al 2009, which surveyed 3146 earth scientists and found that about 90% of “active publishers” and 97.4% of what I’ve termed climate “super-experts” agreed that “human activity is a significant contributing factor” to climate disruption. Or Anderegg et al 2010, which used an entirely different method (not a poll, but rather a survey of publications by climate scientists) to conclude that

97–98% of the climate researchers most actively publishing in the field support the tenets of ACC outlined by the Intergovernmental Panel on Climate Change, and (ii) the relative climate expertise and scientific prominence of the researchers unconvinced of ACC are substantially below that of the convinced researchers.

The order in which questions are asked, the exact wording of the questions, the exact wording of the answers – all of these things have an impact on the results of a given survey. If that weren’t the case, then there wouldn’t be identifiable ideological biases in political polling agencies and every poll would have the exact same outcomes. (The links to each of the polls are in the OP above)

I dove into polling details as a result of coming across a horrible poll a few years back, and I’ve been analyzing polls off and on ever since. If you’re interested in an examination of a really bad poll, check out my analysis of a poll written by Steve Milloy for DemandDebate.com here. I also know that Doran et al 2009 and Anderegg et al 2010 have their detractors, but I deal with a large number of those criticisms here.

Your Iraq WMDs illustration doesn’t make sense to me. You’re equating inexpert opinion stoked by media mistakes and misrepresentations (we knew that Iraq wasn’t tied to 9/11 within weeks after it happened, but much of the media never corrected their original errors) with expert opinion on a scientific subject. They’re not even remotely equivalent situations.

If you don’t like the Paris Hilton comparison, fine. Would you automatically assume that Tom Wysmuller, who is a meteorologist and signed the letter, was qualified to fly the shuttle? Would you assume Cunningham, the pilot, is qualified to design, build, test, and install the shuttle’s ceramic tiles? Of course you wouldn’t. And it’s not because Cunningham wasn’t a good pilot, or because Wysmuller isn’t good at predicting the weather – it’s because without demonstrated proof that Wysmuller was qualified to be a pilot and that Cunningham was qualified to design and install ceramic tiles, you’d be putting lives at risk.

So why would you assume that Cunningham or Schmitt or any of the other 49 signers is qualified to speak about climate disruption? You shouldn’t. Basic knowledge of science is not enough to be qualified. Advanced knowledge of science in an unrelated field is not enough to be qualified. And PhDs go stale if you don’t keep refreshing your knowledge by keeping up with the latest research in your field.

I don’t really care if you or the signers are insulted by the comparison, Nixak, because the comparison is accurate.

In order to avoid going to tit for tat ad-infinitum, ‘Let’s Cut to the Chase’ here. Since you keep referring to this letter signed by these 49 ex-NASA folks, criticizing Jim Hansen’s GISS’ climate modeling methodology used to claim dire future predictions re global-warming- as ‘Naive &/or DisHonest, This seems to imply that some or most of these 49 are [Naive??? 49 ex-NASA vets are naive about the inner-working of NASA??- I Don’t Think So!] DisHonest! So are you ready to back that up??? Are you ready to present evidence & make a clear-cut case that the main reason many/most of these 49 people signed this letter is because many/most of them have financial ties to &/or shills for the coal, oil & gas industries??!! If that’s your real point please make your case directly & if its substantiated by sound evidence, I’ll have no problem saying so. Otherwise- Perhaps you should refrain from characterizing them as DisHonest [or even Naive {NOT!]!

Nixak, you have presented a series of erroneous statements and allegations, you’ve refused to respond to reasoned arguments with logical, supported counterarguments of your own, and you’ve not admitted any errors even when they were repeatedly pointed out to you. That suggests that you are not engaged in a good faith debate.

Even now you bring in an entirely new idea in another attempt at a red herring even as you ask me to “cut to the chase.” Whether or not any or all of the 49 signers are, as you described them, “shills for the coal, oil, & gas industries” does not matter. What matters is the content of the letter, the sheer number of egregious scientific errors of fact contained within the letter, and the fact that 49 people who really should know better signed it.

I stand by the detailed, supported, step-by-step arguments I make in the original post, and that I have reiterated and clarified repeatedly in the comments:

The letter makes numerous errors of scientific fact.
The letter’s author(s) is either naive about the state of climate science or is dishonestly misrepresenting the state of the science for some unknown reason.
All the letter’s signers who were not authors were either misled into signing it, did so out of personal or institutional loyalty to Johnson Space Center, or are ignorant (naive) of the science. It is also possible that some of them might agree with the letter’s unnamed author(s) that it’s acceptable to dishonestly misrepresent the objective facts about climate science, but until that’s been proven on an individual basis, I refuse to ascribe that level of ethical failure to anyone.

Nixak: Here’s the substance of what I said to Brian yesterday. I know there are genuine skeptics out there, but let’s be honest. How many? Are there questions to be answered? Yes. Are there places we need more data and research? Yes, always. But from where I sit, the questions are mainly about how and how much and what next. Are there REALLY credible doubts remaining about a) the climate is changing, and b) a key driver is human activity? The consensus among scientists is overwhelming on those questions.

If there are X people who call themselves skeptics, the number of ACTUAL skeptics in that crowd is what, .001% of the total? Nearly all “climate skeptics” are, in fact, denialists.

We all operate with assumptions in life. One of mine is that if you call yourself a climate skeptic, odds are awfully damned good that you’re not a skeptic at all. You’re either an ideologue, an idiot or a sock puppet.

Or all of the above. Not sure which applies to you, but our comment space at S&R is reserved for good faith exchanges. All you’re doing is wasting the time of people who can tell the difference between a fact and an oil industry PR talking point.

Sam Smith quote} ‘If you call yourself a climate skeptic, odds are awfully damned good that you’re not a skeptic at all. You’re either an ideologue, an idiot or a sock puppet. Or all of the above. Not sure which applies to you, But I know the difference facts & an oil industry PR talking point.’ {

Answer to that insinuation about me: NONE OF THE ABOVE! I’ve never worked for / had ties to the coal, oil, gas, &/or nuke industries [unlike Head of the IPCC Pachuari who once had ties to India’s Oil & gas industries even while IPCC’s head].

This author has in effect insinuated these 49 ex-NASA vets are dishonest! YET apparently he’s NOT prepared [able] to back that accusation up w a fact based case [except perhaps for Harrison Schmitt]. It’s simply ain’t a credible argument that 49 ex-NASA astronauts, administrators, scientists [including a meteorologist] & technical specialists w advanced science &/or technical degrees & a combined total of OVER 1000YRS at NASA- could all be ignorant / naïve about science – especially coming from a division of NASA [IE: GISS]. I suspect some/many of these 49 actually know Jim Hansen [&/or his colleagues at GISS] & likely have worked him [them] on occasion. I don’t think you 2 can make that claim [feel free to correct me if you do know Hansen].

RE: This screed that unless you’re a climatologist you have nothing to say worth listening to RE: the theory of man-made CO2 caused ‘global-warming [no matter if you have advanced Science &/ technology degrees- which sounds a bit snobby & elitist]- Are you saying that this also applies to IPCC Head RK-Pachuari- who is NOT a climatologist [nor meteorologist, ocean / Earth-environmental scientist]- & to Al Gore who’s has no formal back-ground in any scientific field?? – [Gore is a Famous {IE: celebrity} politician who in ‘Inconvenient Truth’ made ‘Global Warming, Hockey-stick graph, & ‘Over-whelming Consensus of Climatologists…’ house-hold terms.]??

I’ll quote PhD physicist & mathematician Freeman Dyson [who says anthropogenic global warming exists] RE this matter because I’m in general agreement w him: } ”I’m not saying the warming doesn’t cause problems, Obviously we should try to understand it. I’m saying that the problems are being grossly exaggerated. They take away money & attention from other problems that are much more urgent. IE: Poverty, infectious diseases, public health & education. Not to mention deforestation, the preservation of living creatures on land and in the seas- and of course war & nuclear & biological weapons…’ – “My objections to the global warming propaganda are not so much over the technical facts, but rather against the way those people [IE: global warming zealots] behave & the intolerance to criticism that many of them have. To reach reasonable solutions of the problems of global warming, all opinions must be heard & all participants must be treated with respect.”
Dr Dyson says that current simulation models of climate fail to account for some important factors, thus their results contain too much error to reliably predict future trends.
“The person who’s most responsible for this overestimate of global warming is Jim Hansen. He consistently exaggerates all the dangers… Hansen has turned his science into ideology…’ {

Moving on to a slightly different topic- Do either or both of you agree w Jim Hansen’s position RE: so-called ‘Green’ Nuke power & carbon capture systems [= so-called ‘Clean’-Coal technology] as solutions to man-made CO2 caused Global-Warming???

In my last comment, I indicated that I thought you might not be debating in good faith. Unfortunately, your comment above proved me right.

I responded in clear, plain language that I was unwilling to ascribe the ethical failure of dishonesty to anyone without proof. I further explained – twice – that naive and/or dishonest claims in a letter doesn’t mean that everyone who signed the letter was naive and/or dishonest, only that the letter’s author(s) was. Yet you incorrectly claim that I’m insinuating all the letter’s signers are dishonest, in direct opposition to my repeated statements.

You’ve written that I’m claiming that the 49 ex-NASA employees are “ignorant/naive about science (emphasis added),” when in fact I’ve never made that claim. I’ve claimed that they are ignorant and/or naive about climate science, but not about science in general.

And now you’re resorting to the same red herring, namely the “appeal to celebrity,” that the letter does and that I demolish in the OP. Freeman Dyson is not a climate scientist and, to the best of my knowledge, has never worked in any climate-related field. He falls into the same category as Tesla with respect to relativity, Kelvin with respect to the age of the Earth, and Jeffreys with respect to plate tectonics. Brilliant men in their own fields who nonetheless were famously wrong when they ventured outside their narrow expertise.

You’re ignoring facts and questions and statements that disagree with your own opinions, Nixak. This demonstrates that you are close-minded and unwilling to debate in good faith. Until such time as you’re willing to open your mind and debate in good faith without the repeated use of glaring logical fallacies, you’re welcome to find some other blog at which to comment.

I’m ended up on this site because- It’s notable that there’s been little in the main-stream media [except for Huf-Post & Yahoo] on this letter by 49 ex-NASA vets. Likewise for the alternative media – IE: the Real News did a 3 recent part series in June on climate-change but the subject of this letter never even came up. I call that a near total news black-out. So I did a Google search RE this letter & one link brought me here.

Apparently you refuse to respond to Al Gore celebrity status as a main advocate [perceived authority] RE: the theory of man-made CO2 caused global-warming- who is a famous politician w NO formal scientific training [FYI: Gore’s far more famous the either Dr Dyson & even most of these 49 ex-NASA vets]- nor will you respond to IPCC Head Pachuari’s lack of expertise in climatology. Got It.